744 lines
17 KiB
C
744 lines
17 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* SR-IPv6 implementation
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*
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* Author:
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* David Lebrun <david.lebrun@uclouvain.be>
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*/
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#include <linux/types.h>
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#include <linux/skbuff.h>
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#include <linux/net.h>
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#include <linux/module.h>
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#include <net/ip.h>
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#include <net/ip_tunnels.h>
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#include <net/lwtunnel.h>
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#include <net/netevent.h>
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#include <net/netns/generic.h>
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#include <net/ip6_fib.h>
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#include <net/route.h>
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#include <net/seg6.h>
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#include <linux/seg6.h>
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#include <linux/seg6_iptunnel.h>
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#include <net/addrconf.h>
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#include <net/ip6_route.h>
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#include <net/dst_cache.h>
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#ifdef CONFIG_IPV6_SEG6_HMAC
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#include <net/seg6_hmac.h>
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#endif
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#include <linux/netfilter.h>
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static size_t seg6_lwt_headroom(struct seg6_iptunnel_encap *tuninfo)
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{
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int head = 0;
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switch (tuninfo->mode) {
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case SEG6_IPTUN_MODE_INLINE:
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break;
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case SEG6_IPTUN_MODE_ENCAP:
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case SEG6_IPTUN_MODE_ENCAP_RED:
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head = sizeof(struct ipv6hdr);
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break;
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case SEG6_IPTUN_MODE_L2ENCAP:
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case SEG6_IPTUN_MODE_L2ENCAP_RED:
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return 0;
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}
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return ((tuninfo->srh->hdrlen + 1) << 3) + head;
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}
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struct seg6_lwt {
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struct dst_cache cache;
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struct seg6_iptunnel_encap tuninfo[];
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};
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static inline struct seg6_lwt *seg6_lwt_lwtunnel(struct lwtunnel_state *lwt)
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{
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return (struct seg6_lwt *)lwt->data;
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}
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static inline struct seg6_iptunnel_encap *
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seg6_encap_lwtunnel(struct lwtunnel_state *lwt)
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{
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return seg6_lwt_lwtunnel(lwt)->tuninfo;
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}
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static const struct nla_policy seg6_iptunnel_policy[SEG6_IPTUNNEL_MAX + 1] = {
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[SEG6_IPTUNNEL_SRH] = { .type = NLA_BINARY },
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};
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static int nla_put_srh(struct sk_buff *skb, int attrtype,
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struct seg6_iptunnel_encap *tuninfo)
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{
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struct seg6_iptunnel_encap *data;
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struct nlattr *nla;
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int len;
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len = SEG6_IPTUN_ENCAP_SIZE(tuninfo);
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nla = nla_reserve(skb, attrtype, len);
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if (!nla)
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return -EMSGSIZE;
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data = nla_data(nla);
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memcpy(data, tuninfo, len);
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return 0;
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}
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static void set_tun_src(struct net *net, struct net_device *dev,
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struct in6_addr *daddr, struct in6_addr *saddr)
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{
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struct seg6_pernet_data *sdata = seg6_pernet(net);
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struct in6_addr *tun_src;
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rcu_read_lock();
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tun_src = rcu_dereference(sdata->tun_src);
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if (!ipv6_addr_any(tun_src)) {
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memcpy(saddr, tun_src, sizeof(struct in6_addr));
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} else {
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ipv6_dev_get_saddr(net, dev, daddr, IPV6_PREFER_SRC_PUBLIC,
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saddr);
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}
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rcu_read_unlock();
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}
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/* Compute flowlabel for outer IPv6 header */
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static __be32 seg6_make_flowlabel(struct net *net, struct sk_buff *skb,
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struct ipv6hdr *inner_hdr)
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{
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int do_flowlabel = net->ipv6.sysctl.seg6_flowlabel;
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__be32 flowlabel = 0;
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u32 hash;
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if (do_flowlabel > 0) {
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hash = skb_get_hash(skb);
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hash = rol32(hash, 16);
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flowlabel = (__force __be32)hash & IPV6_FLOWLABEL_MASK;
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} else if (!do_flowlabel && skb->protocol == htons(ETH_P_IPV6)) {
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flowlabel = ip6_flowlabel(inner_hdr);
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}
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return flowlabel;
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}
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/* encapsulate an IPv6 packet within an outer IPv6 header with a given SRH */
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int seg6_do_srh_encap(struct sk_buff *skb, struct ipv6_sr_hdr *osrh, int proto)
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{
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struct dst_entry *dst = skb_dst(skb);
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struct net *net = dev_net(dst->dev);
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struct ipv6hdr *hdr, *inner_hdr;
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struct ipv6_sr_hdr *isrh;
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int hdrlen, tot_len, err;
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__be32 flowlabel;
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hdrlen = (osrh->hdrlen + 1) << 3;
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tot_len = hdrlen + sizeof(*hdr);
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err = skb_cow_head(skb, tot_len + skb->mac_len);
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if (unlikely(err))
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return err;
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inner_hdr = ipv6_hdr(skb);
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flowlabel = seg6_make_flowlabel(net, skb, inner_hdr);
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skb_push(skb, tot_len);
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skb_reset_network_header(skb);
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skb_mac_header_rebuild(skb);
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hdr = ipv6_hdr(skb);
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/* inherit tc, flowlabel and hlim
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* hlim will be decremented in ip6_forward() afterwards and
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* decapsulation will overwrite inner hlim with outer hlim
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*/
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if (skb->protocol == htons(ETH_P_IPV6)) {
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ip6_flow_hdr(hdr, ip6_tclass(ip6_flowinfo(inner_hdr)),
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flowlabel);
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hdr->hop_limit = inner_hdr->hop_limit;
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} else {
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ip6_flow_hdr(hdr, 0, flowlabel);
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hdr->hop_limit = ip6_dst_hoplimit(skb_dst(skb));
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memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
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/* the control block has been erased, so we have to set the
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* iif once again.
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* We read the receiving interface index directly from the
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* skb->skb_iif as it is done in the IPv4 receiving path (i.e.:
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* ip_rcv_core(...)).
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*/
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IP6CB(skb)->iif = skb->skb_iif;
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}
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hdr->nexthdr = NEXTHDR_ROUTING;
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isrh = (void *)hdr + sizeof(*hdr);
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memcpy(isrh, osrh, hdrlen);
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isrh->nexthdr = proto;
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hdr->daddr = isrh->segments[isrh->first_segment];
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set_tun_src(net, dst->dev, &hdr->daddr, &hdr->saddr);
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#ifdef CONFIG_IPV6_SEG6_HMAC
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if (sr_has_hmac(isrh)) {
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err = seg6_push_hmac(net, &hdr->saddr, isrh);
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if (unlikely(err))
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return err;
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}
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#endif
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hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
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skb_postpush_rcsum(skb, hdr, tot_len);
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return 0;
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}
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EXPORT_SYMBOL_GPL(seg6_do_srh_encap);
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/* encapsulate an IPv6 packet within an outer IPv6 header with reduced SRH */
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static int seg6_do_srh_encap_red(struct sk_buff *skb,
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struct ipv6_sr_hdr *osrh, int proto)
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{
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__u8 first_seg = osrh->first_segment;
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struct dst_entry *dst = skb_dst(skb);
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struct net *net = dev_net(dst->dev);
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struct ipv6hdr *hdr, *inner_hdr;
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int hdrlen = ipv6_optlen(osrh);
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int red_tlv_offset, tlv_offset;
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struct ipv6_sr_hdr *isrh;
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bool skip_srh = false;
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__be32 flowlabel;
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int tot_len, err;
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int red_hdrlen;
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int tlvs_len;
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if (first_seg > 0) {
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red_hdrlen = hdrlen - sizeof(struct in6_addr);
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} else {
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/* NOTE: if tag/flags and/or other TLVs are introduced in the
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* seg6_iptunnel infrastructure, they should be considered when
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* deciding to skip the SRH.
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*/
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skip_srh = !sr_has_hmac(osrh);
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red_hdrlen = skip_srh ? 0 : hdrlen;
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}
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tot_len = red_hdrlen + sizeof(struct ipv6hdr);
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err = skb_cow_head(skb, tot_len + skb->mac_len);
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if (unlikely(err))
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return err;
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inner_hdr = ipv6_hdr(skb);
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flowlabel = seg6_make_flowlabel(net, skb, inner_hdr);
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skb_push(skb, tot_len);
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skb_reset_network_header(skb);
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skb_mac_header_rebuild(skb);
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hdr = ipv6_hdr(skb);
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/* based on seg6_do_srh_encap() */
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if (skb->protocol == htons(ETH_P_IPV6)) {
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ip6_flow_hdr(hdr, ip6_tclass(ip6_flowinfo(inner_hdr)),
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flowlabel);
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hdr->hop_limit = inner_hdr->hop_limit;
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} else {
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ip6_flow_hdr(hdr, 0, flowlabel);
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hdr->hop_limit = ip6_dst_hoplimit(skb_dst(skb));
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memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
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IP6CB(skb)->iif = skb->skb_iif;
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}
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/* no matter if we have to skip the SRH or not, the first segment
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* always comes in the pushed IPv6 header.
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*/
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hdr->daddr = osrh->segments[first_seg];
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if (skip_srh) {
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hdr->nexthdr = proto;
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set_tun_src(net, dst->dev, &hdr->daddr, &hdr->saddr);
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goto out;
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}
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/* we cannot skip the SRH, slow path */
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hdr->nexthdr = NEXTHDR_ROUTING;
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isrh = (void *)hdr + sizeof(struct ipv6hdr);
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if (unlikely(!first_seg)) {
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/* this is a very rare case; we have only one SID but
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* we cannot skip the SRH since we are carrying some
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* other info.
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*/
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memcpy(isrh, osrh, hdrlen);
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goto srcaddr;
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}
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tlv_offset = sizeof(*osrh) + (first_seg + 1) * sizeof(struct in6_addr);
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red_tlv_offset = tlv_offset - sizeof(struct in6_addr);
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memcpy(isrh, osrh, red_tlv_offset);
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tlvs_len = hdrlen - tlv_offset;
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if (unlikely(tlvs_len > 0)) {
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const void *s = (const void *)osrh + tlv_offset;
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void *d = (void *)isrh + red_tlv_offset;
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memcpy(d, s, tlvs_len);
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}
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--isrh->first_segment;
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isrh->hdrlen -= 2;
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srcaddr:
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isrh->nexthdr = proto;
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set_tun_src(net, dst->dev, &hdr->daddr, &hdr->saddr);
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#ifdef CONFIG_IPV6_SEG6_HMAC
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if (unlikely(!skip_srh && sr_has_hmac(isrh))) {
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err = seg6_push_hmac(net, &hdr->saddr, isrh);
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if (unlikely(err))
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return err;
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}
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#endif
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out:
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hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
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skb_postpush_rcsum(skb, hdr, tot_len);
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return 0;
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}
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/* insert an SRH within an IPv6 packet, just after the IPv6 header */
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int seg6_do_srh_inline(struct sk_buff *skb, struct ipv6_sr_hdr *osrh)
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{
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struct ipv6hdr *hdr, *oldhdr;
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struct ipv6_sr_hdr *isrh;
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int hdrlen, err;
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hdrlen = (osrh->hdrlen + 1) << 3;
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err = skb_cow_head(skb, hdrlen + skb->mac_len);
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if (unlikely(err))
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return err;
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oldhdr = ipv6_hdr(skb);
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skb_pull(skb, sizeof(struct ipv6hdr));
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skb_postpull_rcsum(skb, skb_network_header(skb),
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sizeof(struct ipv6hdr));
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skb_push(skb, sizeof(struct ipv6hdr) + hdrlen);
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skb_reset_network_header(skb);
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skb_mac_header_rebuild(skb);
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hdr = ipv6_hdr(skb);
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memmove(hdr, oldhdr, sizeof(*hdr));
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isrh = (void *)hdr + sizeof(*hdr);
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memcpy(isrh, osrh, hdrlen);
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isrh->nexthdr = hdr->nexthdr;
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hdr->nexthdr = NEXTHDR_ROUTING;
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isrh->segments[0] = hdr->daddr;
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hdr->daddr = isrh->segments[isrh->first_segment];
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#ifdef CONFIG_IPV6_SEG6_HMAC
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if (sr_has_hmac(isrh)) {
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struct net *net = dev_net(skb_dst(skb)->dev);
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err = seg6_push_hmac(net, &hdr->saddr, isrh);
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if (unlikely(err))
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return err;
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}
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#endif
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hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
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skb_postpush_rcsum(skb, hdr, sizeof(struct ipv6hdr) + hdrlen);
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return 0;
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}
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EXPORT_SYMBOL_GPL(seg6_do_srh_inline);
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static int seg6_do_srh(struct sk_buff *skb)
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{
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struct dst_entry *dst = skb_dst(skb);
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struct seg6_iptunnel_encap *tinfo;
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int proto, err = 0;
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tinfo = seg6_encap_lwtunnel(dst->lwtstate);
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switch (tinfo->mode) {
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case SEG6_IPTUN_MODE_INLINE:
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if (skb->protocol != htons(ETH_P_IPV6))
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return -EINVAL;
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err = seg6_do_srh_inline(skb, tinfo->srh);
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if (err)
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return err;
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break;
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case SEG6_IPTUN_MODE_ENCAP:
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case SEG6_IPTUN_MODE_ENCAP_RED:
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err = iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6);
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if (err)
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return err;
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if (skb->protocol == htons(ETH_P_IPV6))
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proto = IPPROTO_IPV6;
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else if (skb->protocol == htons(ETH_P_IP))
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proto = IPPROTO_IPIP;
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else
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return -EINVAL;
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if (tinfo->mode == SEG6_IPTUN_MODE_ENCAP)
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err = seg6_do_srh_encap(skb, tinfo->srh, proto);
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else
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err = seg6_do_srh_encap_red(skb, tinfo->srh, proto);
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if (err)
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return err;
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skb_set_inner_transport_header(skb, skb_transport_offset(skb));
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skb_set_inner_protocol(skb, skb->protocol);
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skb->protocol = htons(ETH_P_IPV6);
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break;
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case SEG6_IPTUN_MODE_L2ENCAP:
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case SEG6_IPTUN_MODE_L2ENCAP_RED:
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if (!skb_mac_header_was_set(skb))
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return -EINVAL;
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if (pskb_expand_head(skb, skb->mac_len, 0, GFP_ATOMIC) < 0)
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return -ENOMEM;
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skb_mac_header_rebuild(skb);
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skb_push(skb, skb->mac_len);
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if (tinfo->mode == SEG6_IPTUN_MODE_L2ENCAP)
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err = seg6_do_srh_encap(skb, tinfo->srh,
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IPPROTO_ETHERNET);
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else
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err = seg6_do_srh_encap_red(skb, tinfo->srh,
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IPPROTO_ETHERNET);
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if (err)
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return err;
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skb->protocol = htons(ETH_P_IPV6);
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break;
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}
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skb_set_transport_header(skb, sizeof(struct ipv6hdr));
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nf_reset_ct(skb);
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return 0;
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}
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static int seg6_input_finish(struct net *net, struct sock *sk,
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struct sk_buff *skb)
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{
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return dst_input(skb);
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}
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static int seg6_input_core(struct net *net, struct sock *sk,
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struct sk_buff *skb)
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{
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struct dst_entry *orig_dst = skb_dst(skb);
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struct dst_entry *dst = NULL;
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struct seg6_lwt *slwt;
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int err;
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err = seg6_do_srh(skb);
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if (unlikely(err))
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goto drop;
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slwt = seg6_lwt_lwtunnel(orig_dst->lwtstate);
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local_bh_disable();
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dst = dst_cache_get(&slwt->cache);
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if (!dst) {
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ip6_route_input(skb);
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dst = skb_dst(skb);
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if (!dst->error) {
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dst_cache_set_ip6(&slwt->cache, dst,
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&ipv6_hdr(skb)->saddr);
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}
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} else {
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skb_dst_drop(skb);
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skb_dst_set(skb, dst);
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}
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local_bh_enable();
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err = skb_cow_head(skb, LL_RESERVED_SPACE(dst->dev));
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if (unlikely(err))
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goto drop;
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if (static_branch_unlikely(&nf_hooks_lwtunnel_enabled))
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return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
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dev_net(skb->dev), NULL, skb, NULL,
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skb_dst(skb)->dev, seg6_input_finish);
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return seg6_input_finish(dev_net(skb->dev), NULL, skb);
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drop:
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kfree_skb(skb);
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return err;
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}
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static int seg6_input_nf(struct sk_buff *skb)
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{
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struct net_device *dev = skb_dst(skb)->dev;
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struct net *net = dev_net(skb->dev);
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|
|
switch (skb->protocol) {
|
|
case htons(ETH_P_IP):
|
|
return NF_HOOK(NFPROTO_IPV4, NF_INET_POST_ROUTING, net, NULL,
|
|
skb, NULL, dev, seg6_input_core);
|
|
case htons(ETH_P_IPV6):
|
|
return NF_HOOK(NFPROTO_IPV6, NF_INET_POST_ROUTING, net, NULL,
|
|
skb, NULL, dev, seg6_input_core);
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
static int seg6_input(struct sk_buff *skb)
|
|
{
|
|
if (static_branch_unlikely(&nf_hooks_lwtunnel_enabled))
|
|
return seg6_input_nf(skb);
|
|
|
|
return seg6_input_core(dev_net(skb->dev), NULL, skb);
|
|
}
|
|
|
|
static int seg6_output_core(struct net *net, struct sock *sk,
|
|
struct sk_buff *skb)
|
|
{
|
|
struct dst_entry *orig_dst = skb_dst(skb);
|
|
struct dst_entry *dst = NULL;
|
|
struct seg6_lwt *slwt;
|
|
int err;
|
|
|
|
err = seg6_do_srh(skb);
|
|
if (unlikely(err))
|
|
goto drop;
|
|
|
|
slwt = seg6_lwt_lwtunnel(orig_dst->lwtstate);
|
|
|
|
local_bh_disable();
|
|
dst = dst_cache_get(&slwt->cache);
|
|
local_bh_enable();
|
|
|
|
if (unlikely(!dst)) {
|
|
struct ipv6hdr *hdr = ipv6_hdr(skb);
|
|
struct flowi6 fl6;
|
|
|
|
memset(&fl6, 0, sizeof(fl6));
|
|
fl6.daddr = hdr->daddr;
|
|
fl6.saddr = hdr->saddr;
|
|
fl6.flowlabel = ip6_flowinfo(hdr);
|
|
fl6.flowi6_mark = skb->mark;
|
|
fl6.flowi6_proto = hdr->nexthdr;
|
|
|
|
dst = ip6_route_output(net, NULL, &fl6);
|
|
if (dst->error) {
|
|
err = dst->error;
|
|
dst_release(dst);
|
|
goto drop;
|
|
}
|
|
|
|
local_bh_disable();
|
|
dst_cache_set_ip6(&slwt->cache, dst, &fl6.saddr);
|
|
local_bh_enable();
|
|
}
|
|
|
|
skb_dst_drop(skb);
|
|
skb_dst_set(skb, dst);
|
|
|
|
err = skb_cow_head(skb, LL_RESERVED_SPACE(dst->dev));
|
|
if (unlikely(err))
|
|
goto drop;
|
|
|
|
if (static_branch_unlikely(&nf_hooks_lwtunnel_enabled))
|
|
return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net, sk, skb,
|
|
NULL, skb_dst(skb)->dev, dst_output);
|
|
|
|
return dst_output(net, sk, skb);
|
|
drop:
|
|
kfree_skb(skb);
|
|
return err;
|
|
}
|
|
|
|
static int seg6_output_nf(struct net *net, struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
struct net_device *dev = skb_dst(skb)->dev;
|
|
|
|
switch (skb->protocol) {
|
|
case htons(ETH_P_IP):
|
|
return NF_HOOK(NFPROTO_IPV4, NF_INET_POST_ROUTING, net, sk, skb,
|
|
NULL, dev, seg6_output_core);
|
|
case htons(ETH_P_IPV6):
|
|
return NF_HOOK(NFPROTO_IPV6, NF_INET_POST_ROUTING, net, sk, skb,
|
|
NULL, dev, seg6_output_core);
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
static int seg6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
if (static_branch_unlikely(&nf_hooks_lwtunnel_enabled))
|
|
return seg6_output_nf(net, sk, skb);
|
|
|
|
return seg6_output_core(net, sk, skb);
|
|
}
|
|
|
|
static int seg6_build_state(struct net *net, struct nlattr *nla,
|
|
unsigned int family, const void *cfg,
|
|
struct lwtunnel_state **ts,
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
struct nlattr *tb[SEG6_IPTUNNEL_MAX + 1];
|
|
struct seg6_iptunnel_encap *tuninfo;
|
|
struct lwtunnel_state *newts;
|
|
int tuninfo_len, min_size;
|
|
struct seg6_lwt *slwt;
|
|
int err;
|
|
|
|
if (family != AF_INET && family != AF_INET6)
|
|
return -EINVAL;
|
|
|
|
err = nla_parse_nested_deprecated(tb, SEG6_IPTUNNEL_MAX, nla,
|
|
seg6_iptunnel_policy, extack);
|
|
|
|
if (err < 0)
|
|
return err;
|
|
|
|
if (!tb[SEG6_IPTUNNEL_SRH])
|
|
return -EINVAL;
|
|
|
|
tuninfo = nla_data(tb[SEG6_IPTUNNEL_SRH]);
|
|
tuninfo_len = nla_len(tb[SEG6_IPTUNNEL_SRH]);
|
|
|
|
/* tuninfo must contain at least the iptunnel encap structure,
|
|
* the SRH and one segment
|
|
*/
|
|
min_size = sizeof(*tuninfo) + sizeof(struct ipv6_sr_hdr) +
|
|
sizeof(struct in6_addr);
|
|
if (tuninfo_len < min_size)
|
|
return -EINVAL;
|
|
|
|
switch (tuninfo->mode) {
|
|
case SEG6_IPTUN_MODE_INLINE:
|
|
if (family != AF_INET6)
|
|
return -EINVAL;
|
|
|
|
break;
|
|
case SEG6_IPTUN_MODE_ENCAP:
|
|
break;
|
|
case SEG6_IPTUN_MODE_L2ENCAP:
|
|
break;
|
|
case SEG6_IPTUN_MODE_ENCAP_RED:
|
|
break;
|
|
case SEG6_IPTUN_MODE_L2ENCAP_RED:
|
|
break;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* verify that SRH is consistent */
|
|
if (!seg6_validate_srh(tuninfo->srh, tuninfo_len - sizeof(*tuninfo), false))
|
|
return -EINVAL;
|
|
|
|
newts = lwtunnel_state_alloc(tuninfo_len + sizeof(*slwt));
|
|
if (!newts)
|
|
return -ENOMEM;
|
|
|
|
slwt = seg6_lwt_lwtunnel(newts);
|
|
|
|
err = dst_cache_init(&slwt->cache, GFP_ATOMIC);
|
|
if (err) {
|
|
kfree(newts);
|
|
return err;
|
|
}
|
|
|
|
memcpy(&slwt->tuninfo, tuninfo, tuninfo_len);
|
|
|
|
newts->type = LWTUNNEL_ENCAP_SEG6;
|
|
newts->flags |= LWTUNNEL_STATE_INPUT_REDIRECT;
|
|
|
|
if (tuninfo->mode != SEG6_IPTUN_MODE_L2ENCAP)
|
|
newts->flags |= LWTUNNEL_STATE_OUTPUT_REDIRECT;
|
|
|
|
newts->headroom = seg6_lwt_headroom(tuninfo);
|
|
|
|
*ts = newts;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void seg6_destroy_state(struct lwtunnel_state *lwt)
|
|
{
|
|
dst_cache_destroy(&seg6_lwt_lwtunnel(lwt)->cache);
|
|
}
|
|
|
|
static int seg6_fill_encap_info(struct sk_buff *skb,
|
|
struct lwtunnel_state *lwtstate)
|
|
{
|
|
struct seg6_iptunnel_encap *tuninfo = seg6_encap_lwtunnel(lwtstate);
|
|
|
|
if (nla_put_srh(skb, SEG6_IPTUNNEL_SRH, tuninfo))
|
|
return -EMSGSIZE;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int seg6_encap_nlsize(struct lwtunnel_state *lwtstate)
|
|
{
|
|
struct seg6_iptunnel_encap *tuninfo = seg6_encap_lwtunnel(lwtstate);
|
|
|
|
return nla_total_size(SEG6_IPTUN_ENCAP_SIZE(tuninfo));
|
|
}
|
|
|
|
static int seg6_encap_cmp(struct lwtunnel_state *a, struct lwtunnel_state *b)
|
|
{
|
|
struct seg6_iptunnel_encap *a_hdr = seg6_encap_lwtunnel(a);
|
|
struct seg6_iptunnel_encap *b_hdr = seg6_encap_lwtunnel(b);
|
|
int len = SEG6_IPTUN_ENCAP_SIZE(a_hdr);
|
|
|
|
if (len != SEG6_IPTUN_ENCAP_SIZE(b_hdr))
|
|
return 1;
|
|
|
|
return memcmp(a_hdr, b_hdr, len);
|
|
}
|
|
|
|
static const struct lwtunnel_encap_ops seg6_iptun_ops = {
|
|
.build_state = seg6_build_state,
|
|
.destroy_state = seg6_destroy_state,
|
|
.output = seg6_output,
|
|
.input = seg6_input,
|
|
.fill_encap = seg6_fill_encap_info,
|
|
.get_encap_size = seg6_encap_nlsize,
|
|
.cmp_encap = seg6_encap_cmp,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
int __init seg6_iptunnel_init(void)
|
|
{
|
|
return lwtunnel_encap_add_ops(&seg6_iptun_ops, LWTUNNEL_ENCAP_SEG6);
|
|
}
|
|
|
|
void seg6_iptunnel_exit(void)
|
|
{
|
|
lwtunnel_encap_del_ops(&seg6_iptun_ops, LWTUNNEL_ENCAP_SEG6);
|
|
}
|